Updated summary on XMRV/CFS by Dr Charles Shepherd

Dr Charles Shepherd, who is the honorary medical adviser for the ME Association in the UK has written a new update of his summary of "What do we know so far? And what don't we know?" on XMRV in relation to ME/CFS.

I read about it on the "Just Four Quid" blog - the blogger says she wishes she had a time machine and could go forward and see how this all works out. I know what she means - the suspense is killing me!

Well said Catch. I'd drafted this short letter to the MEA, albeit based on the version 3 update, and was going to prepare a more detailed letter to Neil Reily. Not sent as yet. Some of my queries have been answered but I'd still like to see a full explanation in print.

"Dear Tony

I am sure that you share the great excitement of whole ME community over the recent Whittemore Peterson Institute study findings strongly implicating the XMRV retrovirus as a possible cause of ME. You should be aware however that there is also some degree of trepidation that, as with past proposed organic causes of ME, follow up studies may prove to be inconclusive or will fail to replicate the findings of the WPI study leading to research interest flagging. A critical issue is that any further research fully replicates the protocol of the WPI study, most specifically that the patients selected for further study are fully representative of the WPI cohort.

It is therefore with some dismay that I read on the MEA website that the MEA recommend that any further research , including MEA funded studies, should select patients diagnosed using the Fukada definition of CFS. As you are aware the Fukada diagnostic criteria allow the inclusion of patients experiencing chronic fatigue but without other key symptoms such as the post-exercise malaise characteristic of classic 'organic ME'.

It is critical at this early stage that researchers are able to replicate the WPI findings to firmly establish the science. Further research leading to rigorous diagnostic techniques and possible treatment will then follow. Adoption of the more strict Canadian diagnostic criteria for patient selection offers the best chance of confirming the WPI findings. I appreciate that there may not be stored samples from patients diagnosed using the Canadian criteria but we have waited a long time for research such as this and can wait a little longer if it means doing it right. A much better approach would be to carry out prospective studies using patients diagnosed using both the Fukada and Canadian criteria (as with the ME Research UK/Irish ME Trust funded study due to report in spring/summer 2010). In fact selecting subjects in this way, plus recording a ranked list of symptoms, would avoid the risk of failing to find the percentages found in the WPI study and would also allow XMRV rates to be compared to the various 'CFS type illnesses' such as IBS, Fibromyalgia and those with fatigue with no other symptoms.

It is incumbent on the MEA, given the importance of this issue, to provide us all with a full explanation of the reasoning behind the proposed research agenda. A detailed article in ME Essential would be ideal ."